The Mystery of the Three Measurements

One single branch. Three different results. How is this possible?

Official Standard Reference: 1.0 Meter (m)
Teacher's Challenge: Look at the branch above. Anna counted 13, Ben counted 3, and Carlos counted 10. Click on each person to reveal their secret unit standards and decode the mystery!
👩‍🎓

Anna

Counted: 13
🧑‍💻

Ben

Counted: 3
👨‍🏫

Carlos

Counted: 10